1. Field of the Invention
This invention relates to paperboard containers. Such structures of this type, generally, allow for the container to be formed into a self-locking, pail-like container for holding food stuffs.
2. Description of the Related Art
It is known, in the food industry, to employ a paperboard pail which is capable of being self-locking. Exemplary of such prior art is commonly found in the Chinese-food take-out industry. For example, Chinese-food take-out orders are boxed in paperboard pails having a wire handle. Commercial products of this type have been sold by the Fold-Pak Corporation since approximately 1977. While these prior, paperboard pails are capable of containing food, these pails cannot be microwaved if the food needs to be reheated due to the presence of the wire handle. Therefore, a more advantageous container, then, would be presented if the container could be microwaved.
Also, if a food package were to employ the pail container having the wire in a mass production facility, the wire would dramatically slow down the filling lines. Typically, a mass production food filling line is run so that 60 containers per minute are folded, filled and sealed. Clearly, the added production step of attaching the wire handle would adversely affect the speed of the filling lines. Therefore, a further advantageous container, then, would be one which could be easily converted into a container.
In order to avoid the use of the metallic wire, trays were developed that sealed each of the gussets to the side walls. Exemplary of such prior art is U.S. Pat. No. 5,411,204 ('204) to K. F. DeMay, entitled "Reclosable Food Tray and Tray Blank". While the tray of the '204 patent eliminates the use of the metal wire and thus can be put in a microwave oven, the tray also employs the use of adhesives in order to seal the gussets to the side walls. While the adhesives allow for the gussets to be sealed to the side walls, the adhesive may contaminate the food product contained within the tray particularly during heating of the tray and the food product. For example, if a pinhole develops in the tray and the adhesive migrates to the pinhole and into the food stuff, the food may become contaminated or develop an off-taste and/or odor. Also, the use of the adhesive adds to the cost of manufacturing the tray and adds another step in the production of the tray. Finally, upon heating, the adhesive may break down, melt and allow the gussets to become dislodged from the sidewall panels. Therefore, a still further advantageous container, then, would be presented if the use of the adhesives could be eliminated.
It is apparent from the above that there exists a need in the art for a paperboard, pail-like container which is self-locking and easily converted, and is capable of being put in the microwave oven, but which at the same time avoids the use of adhesives. It is the purpose of this invention to fulfill this and other needs in the art in a manner more apparent to the skilled artisan once given the following disclosure.